September/October 2011
Your Letters

Get to know people

When I first started as an engineer, I had an aversion to networking. In fact, I was downright ALLERGIC to it.

So, what changed? For one thing, I realized rather quickly that the engineering community here thinks like a small town-everyone knows everyone. If I hoped to gain (and retain) employment, I'd better get to know some people. The other thing that happened was that I became more confident as I advanced in my profession. Although I still dislike crowds, I can and will carve out small groups to speak with at an event. (One thing I've been doing to improve that skill is attending a women's networking event every month.)

Another good tool is social networks. You can make a lot of long distance professional acquaintances on LinkedIn and Facebook. But ... social networking via computer is not and cannot ever completely replace the need for meeting people face to face.

Karen D. Morton, P.E.

Letter in reference to July/August InTech "The Final Say"

 

The complete package

In 1968, GM wrote a specification for a programmable control system, which could replace relay logic. The timing for this spec was right, as a group of designers led by Dick Morley was already working on a design for what became the Modicon 084. GM purchased this Programmable Controller (later known as Programmable Logic Controller), and the PLC is now an immeasurably important technology throughout the world of manufacturing.

PLCs and Distributed Control Systems (DCS) routinely interact with plant operators through computer-based, graphic, Human Machine Interfaces (HMI). The development of the HMI has evolved over a number of operating systems including unique proprietary systems, Unix, BSD, DOS, Windows, and Linux. The most widely used HMIs and arguably the most advanced run on Windows.

One difficulty presented by the Windows operating platform is the rate at which the OS changes. HMI developers exhibit so much time lag while trying to release stable updates that they can easily be an entire release behind.

As a systems integrator, I can say that we are currently (August 2011) supporting the new installation of systems on Windows XP. Last week, we had to scramble to find a copy of Windows 7 with no service packs. Service Pack 1 has already been released, so this will become more difficult over time.

Now, I believe the time is right for a large corporation to write a specification that states that the HMI software will be distributed with the operating system included. The specification for the OS should include all the necessary features: networking, memory management, graphics support, security, licensing, etc. From now on, when HMI software is sold, it can be sold as a complete package. When, in the future, a computer fails after many years of service, there will be a viable path for rebuilding the same system on new hardware.

I think the most obvious response to such a demand would be a system based on BSD or Linux. Both platforms are mature and have many developers worldwide to help out. However, I also think that Microsoft could continue to dominate this area by simply licensing the source code for their older operating systems at the end of their normal support cycles.

Either way, industrial control systems would gain more long-term stability and reliability because developers could continuously improve their own programs instead of playing catch-up to the most recent releases for a platform over which they have no control.

John Pilman,Senior Project Engineer